/*
int
parse four 4
parse five 5
parse six 6
noparse seven Answer 1
*/

/* Test that omitting the result expression is permitted if the rule or an
 * alternative is a single call. */

Answer <- Digit

Digit <- Four / f:Five -> f / Six

Four <- "four" -> 4
Five <- "five" -> 5
Six <- "six" -> 6
